Internal-combustion engine



rs March 20, 1945. E. H. OBRIEN 2,371,911

' INTERNAL- COMBUSTION ENGINE Filed July so, 1943 s Sheets-Sheet 1 March 20, 1945.

E ."H. O'BRIEN INTERNAL-COMBUSTION ENGINE 'Filed July so, 1943 5 Sheets-Sheet 3 March 20, 1945. E. H. OBRIEN 2,371,911

INTERNAL- COMBUSTION ENGINE Fiied July 30, 1943 5 Shee'ts-Shget 4 March 20, 1945.

. E. H.- O'BRIEN INTERNAL-COMBUSTION ENGINE 5 Sheets-Sheet 5 7 Filed July so, 1943 w w 7 .7 fi/ 0 0 co 9 6 7 m w m w A/ F 1 v 3 6 0 5 3 0 6pm W6; H a v 7 A Y 0% w 6 3 i w 5W4 1% (Wm Patented Mar. 20, 1945 UNITED STATES PATENT OFFICE l Edmund Hale OBrien, Kansas City, Mo.

Application July 30, 1943, Serial No. 496,816

5 Claims. v (Cl. 123--57) My invention relates to improvements in internal combustion engines.

.It relates particularly to engines of the tw cycle reciprocating piston type, and is well adapt-- ed for use in propelling airplanes.

The novel features of my invention are applicable to engines of the single piston type or to the multiple piston type having cylinders ar ranged in tandem with the pistons attached to a single connecting rod through a single piston rod.

The object of my invention isthe provision of a novel engine of the kind described, which is simple, strong, durable, not likely to get out of order, which exerts a maximum of power with a minimum of material in its construction, and which is eflicient in its operation.

, Another object of my invention is the provision of novel means for heating or cooling the parts exposed to the heat resulting from the exploded charges. v

Still another object .of my invention is the provision of a novel arrangement of the fuel supply, ignition and exhaust mechanism.

The novel features of my invention are hereinafter fully described and claimed.

In the accompanying drawings, which illustrate my invention, I

Fig. l is a central longitudinal vertical sectional view of the form of my invention provided with cylinders arranged in tandem, showing the pistons at the lower end of their stroke, with some 7 parts omitted.

positioned when the piston heads areat the upper end of their stroke.

Fig. 5 is a view of the structure shown in Fig. 4, but in a direction at right angles thereto, parts being shown in longitudinal vertical section, and other parts in side elevation, the parts being positioned as when the piston heads are at the upper end of their stroke.

Fig. 6 is a longitudinal vertical sectional View, with the parts positioned as shown in Fig. 4 and Fig. 5, viewed in the same direction as in Fig. 5.

Fig. 7 is a cross section on the line 1-1 of Fig. 6.

Fig. 8 is a section on the line 88 of Fig. 6.

Fig; 9 is a longitudinal vertical sectional view of a modified formof my invention employing but one explosion cylinder and one piston head.

' cation of my invention.

. Fig. 12 isan enlarged view showing the upper part of the upper cylinder, of the type, shown in Fig. 1, shown in vertical section; a part of the crank shaft, in side elevation; the intake and exhaust valves being shown in vertical section in the open positions; and the mechanism for open ing said valves, shown-mou'ntedon the cylinder head and connected with the crank shaft, some parts in vertical section, others in side elevation, and parts omitted.

and' having fastened to and between them by bolts 3 a head 4 common to both.

The head 4 has a tubular extension 5 extending into and concentric with the cylinder I and hav: ing open ends. The'upper end of the cylinder I -has fastened to it-by bolts 6 a head I.

The lower end of the lower cylinder 2 has a head 8 provided with a tubular extension 9, open at its ends, and extending into and concentricwith the cylinder 2.

The head 8 is fastened by bolts I0 to the cylinder 2 andto the upper end of cross head guide supporting means comprising a vertical cylinder II,' the lower .end of which is fastened by bolts I2 to-the periphery of a horizontal cylindrical crank case I3, having a peripheral opening I l registering with the cylinder. II and through which extends a connecting rod I5 pivoted to the crank I6 of a crank shaft I I rotatable in and extending through heads 18 at the ends of the crankcase I3. v x

A wrist pin I9 is reciprocative at its ends respectively between two pairs of cross head guides ZIifastened to opposite inner sides of the cylinder II. The connecting rod I5 is pivoted to the wrist pin I9, adjacent to the middle thereof, and the wrist pin is parallel with the crank shaft IT.

The explosion cylinders I and 2 are shown as being air cooled, each being provided with spaced ner cylinder 24, open at its lower end and tightly reciprocatively fitted on the tubular extension 5. The upper end of the inner cylinder 24 is closed and has attached to it the upper end of the upper part of a two part piston rod, the lower part 26 of which has its upper end screwthreaded and fitted in a threaded opening 21 in the lower end of the part 25. The part 25 of the piston rod extends downwardly through the inner cylinder 24, its lower portion being of enlarged diameter and snugly reciprocativelyfittedJinthe inner cylinder 24. The lower part 26 of the piston rod is reciprocative through the tubular extension 9, and. has its lower end provided with a U shaped hearing 28 operatively engaging the wrist'ipinv 1:3 at: opposite sides of the connecting rod l5...

Reciprocatively fitted in the lower cylinder 2 is another piston head 29, the uppenendiof; which; is integrally connected to and reciprocative with the lower end of the upper part 25 of the piston rod. The piston head 29 has an. inner; cylinder 3!] reciprocatively snugly fittedomthetubulanextension 9. The piston: headsw Band. 29' move simultaneously in' like directions. with; the piston. rod 25-26. To prevent airg pressurerresistancer in the inner. cylinders 24 andlifllduringrthevre ciprocation of thepiston' heads 29.: and-29; anairpassage 3l=provided1in the; parts; 25- and 26 of; the piston: rod; communicates: at. its upper? end: with the inner cylinder 24;. through the. tubular extension .5; and .at: its lower -end witlr the interior of the cylinder: IL. An; opening;v 32* in the side; of. the portion. 26: commurficateawitmthe; passage. 31 and. with the: inner? cylinder: an: at thezpistom head 29.

For simultaneously-supplymgs explosive charges to theexp'losiom cylinders: t and2 at llke ends of the pistonheadslhrand :29, a supply conductor 33 is connected at one endtoanaintakeivalve 34inthecylinderhead'l, Fig: 121 The Othenendcif tlie conductor; 33 is connected to-a compressor-44 which is;connected' by; apipe- 35 to a carburetor" 36. which is supplied" by any suitahle means, notshown, with" explosivemateria'h A branch pipe 31" from: the eonductor'33' communicates with theinterior of the explosion cylinder l at a point where it will discharge in to the cylinder I below the: piston head ng when the latter is'at the end of'its upperstroke; as in Fig. 4;

Another branch pipe 38 from the conductor- 33- communicates with the interior" of the explosion cylinder 2 at a point where it willdischarge into cylinder 2 below the piston head 29, when the latter is at the upper endof its stroke, as in 4.

A third branch pipe 39from the conductor 33 communicates with the explosion cylinder 2 at a point where it willdischargeinto the cylinder when the piston head 29 is in the lowermost position, shown in Fig. -I. The intake valve34iha-s controlling means, shown in Figs. 12 and; 13,. for causing it to open when. the. piston head; 23- is in the lowermost position. shown in Fig. 1.

A spark plug. 40 is mountedin the cylinder. head I, and another spark plug; 4 I; extended through.

pistonheadi 29. i i: mounted.-

An exhaust valve 44; see/Fig. 12, is: in the cylindenhead. l tonexhausting the: spent gas-fromabove thepiston: head 23;,when the:,lat-

' ductor 46 communicates with the cylinder 2 at a point above the piston head 29, when the latter is in the lower position, shown in Fig. 1.

m Means accessory to the annular peripheral flanges. 22 anthecylinders l and 2 are provided for cooling the said cylinders and the parts thereim Referring: to; Figs. 6, '7 and 8, the inner cylinder 2.4. of the piston head 23 is encircled by a chamber 49 having an air intake opening 50 extending-'throughithe peripheral. walk of the: piston head. An air discharge opening. 5| is provided:

- which wall has in-it;-jdiame.trically"opposite from.

the:- opening or." air passage 55; an air discharge passage or dischargezopeningafifi;

In; the chamber;- 54; are. also provided upper radial partitions 5! extending from the innercylinder 3E to the peripheral wall of the piston headf29. Below and; spaced from: the partitions 51 are partitions 58:'respectively'parallel with the partitionsfi].

When the piston. heads 23' and; 23 are at the limit of: their upper stroke; as; shown. in Fig; 6, the air intake openings 59 and: 55? registerwith. twp.= openings: 59. and 6.0. the sidewalls Off the explosion: cylinders l: and: 2; in which last two named openings arerightly respectively-fitted the: ends:of;anzairrconductingpipe 5!, which is supplied by air under pressure by a blowerfiZ.

When; the piston: heads and 29. are at the limit of their upper stroke, as shown in. Fig. 6;. the. discharge openings 51 and 55 respectively register'with' two discharge openings 63 and 64 provided: through the walls: of thecylinders" i and 2rrespectively.

Thus once during each reciprocation of; the pistonaheads 23 and; 29, cool air under pressure is? forced-by: the blower 62': through the airpipe 6i, intake openings 50.. and 55., chambers 49 and.

54,. discharge openings 51' and 58, and. through discharges openings 53 and G4 to theatmosphere, whereby the engine is internally thoroughly cooled- In the operation of: the engine, assuming the parts to. heinthezpositions shown inFigs. 4 and'53 with: the pistonv heads 23: and 291 in their uppermost positions, and explosive charges respective-- ly in theicylinders kand.2:abovezthet-piston heads 23 and 29; the spark plugs 4 and 42 are operated to explode the charges, fresh charges, having just previouslybeen' admitted into. the cylinders i and 2, below the piston heads 23 and 29, through the supply branch pipes 3! and 38.

The exploded charges above the piston heads 23 and 29 force them downwardly with the piston rod '2526 to the lowermost position shown in Fig. 1, compressing-the chargesbelow the piston heads, at which time the exploded charges above the piston heads 23 and 29 escape through the exhaust valve 44 and the exhaust pipe 48, at which time fresh charges enter the cylinders I and 2 through the intake valve 34 and the sup ply pipe 39.

The spark plugs 4| and 43 are then operated to explode the compressed charges under the piston heads, forcing the latter upwardly, with the piston rod 25-26, and compressing the charges above the piston heads, thus completing a'cycle.

' As has been explained, when the piston heads 23 and 29 reachthe upper position shown in Figs. 4 and 6; cool air is discharged through 'the chambers 49 and 54. i

While in the drawings, but one set of explosion cylinders I and 2 is shown mounted in tandem on the periphery of the cylindrical crank case 2,

one or more duplicates of this structure maybe similarly mounted thereon, disposed in the same transverse plane as this one, and in spaced ra dial positions.

' In Figs. 9 and 10, is shown a modification of my invention, in which but one explosion cylinder, I and one piston head 23' are employed.

The cylinder I corresponds to the cylinder l of cylinder 24 provided in a piston head 23 recipro-' cative in the cylinder I'. The cylinder head 4 is fastened by bolts 3 to the lower end of the explosion cylinder ,I, and

to the upper end of a vertical tubular cylinder I I having on its inner side diametrically opposite pairs of cross head guides 29. As in the other form of my invention, the lower end of the cylinder II is fastened by bolts I2 to the periphery of a crankcase I3 having a peripheral opening I4 registering with the interior of the cylinder 1 I;-

A wrist pin I9 having its erlds reciprocatively The lower end of the piston rod 25' is bifurcated and operatively engages the wrist pin I9. Th piston rod 25' is provided with a longitudinal air passage 3| communicating with the in terior of the inner cylinder '24 and with the interior of the cylinder I I.

The cylinder head I has mounted in it an in take valve 34 and an exhaust valve 44. An air conductor 33 is connected to the intake valve 34 and to a compressor 34', connected by a pipe 35 to a carburetor 36, as in the other form of my invention.

-A branch pipe 31 from the conductor 33 exthe piston head 23.

. Connected with the exhaust valve 44 is a discharge pipe 45 to which is connected an exhaust pipe-46 which extends through theside wall of the cylinder I' at a point below the piston head 1 23 when the latter is at the upper end of its stroke. a

The piston head 23 has the chamber 49 between the inner cylinder'24 and, the peripheral wall of the piston head 23, and the two rows of radial partitions 52 and 53, as in the other form of my invention, and the same means are provided for supplying cold air to the chamber 49, as in the other form of my invention.

The operation of the piston head 23 and parts connected therewith, and the operations of supplying charges of propelling fluid to the cylinder- I and the compression, exploding and exhausting of the charges, corresponds to those described in connection with the other form of my invention.

In both forms of the invention, shown in Figs. 4 and 9, the engines have been described as be ing operated above and below the piston heads on the two cycle type, however, if desired, the engines may each be operated above the piston head on the four cycle type, by employing the usual type of mechanism. for operating the intake valve 34 and the exhaust valve 44, and the spark plug-40 on the four cycle type. In such operation, when the piston head 23 moves downwardly, the intake valve 34 will be opened and the exhaust valve 44 closed, thus admitting an explosive charge into the explosion cylinder above the piston'head 23.

When the piston head 23 moves upwardly, the charge above the piston head will be compressed, thervalves 34 and 44 being closed during such upward movement. When the piston head reaches the uppermost position, shown in Figs. 4 and 9, the spark plug 40 will be operated to explode the compressed charge, thus forcing the piston head downwardly. On the up stroke, the intake valve will be closed and the exhaust valve opened, thus exhausting the exploded chargeand completing the cycle.

During this four cycle type of operation, the

engines, below the piston heads will operate on the two'cycle type.

When the engines are used in very cold climates, or flown at very high altitudes, the blower .62 may be employed to force a heating fluid, as

hot air, through the pipe 6|,through the explosion cylinder walls and against and through the piston'heads to heat, instead of cooling the cylinders and piston heads, to'the proper best operating temperatures.

In the modified form of my invention, shown in Fig. 11, is shown a portion of a usual single cylinder, single piston head four cycle type of explosive engine provided with a mechanism of I my invention adaptedfor discharging a heating orcooling fluid, as hot or cold air, through the explosion cylinder wall, against and around the piston head again through the cylinder wall to the atmosphere. I

Referring to Fig. 11,- I designates the explosion wall shown in Fig.4, having the upper head t in; which are. mounted the intake valve. 34.. the;

exhaust valve 44 and the spark plug 4.0;, said. valves and spark: plug having, the. usual. means for operating them on the. four cycle type;

Thepiston head 61. has pivoted to; it: inL usual.

manner one end of, a. usual connecting rod the other end of which is-pivoted tqthe crank N5 of the driven crank shaft H, mounted; in the cold air to. an annular groove 6.8 provided; in-the periphery of the piston head 61, and communieating with thedischarge end. of the pipe. 61. and: with an opening 69 through the-cylinder wall 1" communicating with the atmosphere diametrically opposite-the cylinder wall openingin which is fitted the discharge end of the; pipe. 61..

The. heating or cooling fluidwhich is discharged through the-pipe 6L. annular groove 68.- and. dis-.- charge opening 68, isrof such temperature as will retain the piston head 61 at the proper operating, temperature; The cylinder wall I maybe'provided also with the. usual. peripheral flanges 22; for cooling the cylinder by contact. with. theexternal atmosphere.

The. annular groove 68. is disposed. in: the: per riphery of. thepiston'head 6.1 so. asto. be in con.- stant communication; with the; pipe BI, and; the. pipe 6 I. is located below the limit-of. stroke. downward. of theusual piston rings. 10. disposed: in the" upper. peripheral portion ofthe piston head. 6,1.

In Figs. 12 and. 13., isshown mechanism for-op.-

erating the intakevalve. 3.4- and the; exhaust valve;

44 on a two. cyclebasis.

The intake valve comprisesa tubular cylindricalcasing 34, closed atLits upper end and having anopen lower end inwardly beveled, and adapt-- ed to have.- seated therein. the beveled edge of. a.

member 13 having a notched; perimeter fastened.

to the inner. wall of the casing 34. The valve stem 12 extends upwardly from the guiding-mem her 13. to. and. through a, central vertical hole in the closed upper end of the; casing 34,. in

which hole the stem 12 is snugly slidablyfittedr so as-to project at all times above the top of the casing 34.

For. normally forcing the valve disk H upwardly to its closed position, shown. in: Fig. 1, a coil spring 14 encircles. the. stem 12; and bears at its lower end against the; upper side. of they guiding member T3, the. upper endof the. spring: bearing against the under side of a. collar. 15'

fastened on: the stem 12. The. tension. of the spring 14. normally forces thevalve disk H to the closedposition against the. lower end oi the.

casing: 34.. The lower portion. of the valve; OBS.-

ing 34 extends. through. and is tightly fitted in.

a-verticalhole in. the. cylinder head. I. The supplyconductor. 33 has its discharge end tightly fittedv in an opening in one side of the. casing 34 near the upper end thereof, as shown.

The-construction of the exhaust valve and cylinder side wall, corresponding; to the cylinderits. modeof operation corresponds to; that the intake valve 34,..iust; described..

-'I.he exhaustvalve is providedwitha. disk valve 16, avalve stem 11-, a. guiding memb r 18,.a: coil. spring 19: and: a. collar 80, which correspond in structure and. mode of; operation. to the-disk valve. It, stem 12,. guiding member 1.3, coil spring 14 and: collar 15. of the. intake valve, just hereinbefore described.

For opening the intakevalve disk I l, alcam. 8| having, a; tooth. 82- on: its. periphery, for engaging and depressing the valve stem 12, is rigidly mounted; on a. horizontal shaft 83. rotatably mounted in: thevertical; portions 84 of two L shapedbearings having horizontal. portions 85. resting. on. the. topof. the: cylinder head 1, to which. they; are respectivelyfastened: by; two. diametrically OppDE- site: ones. of. the. bolts 6 located. in the vertical central-plane of the: valve; casings 34 and 44'.

For: revolving the. shaft 83 once during. each: revolution of the crank shaft IT, a, sprocket. wheel; 86. rigidly fastened on the. shaft 83 is connected bya sprocket chain belt 81 with a sprocketwheel' 88, of-the diameter of the sprocket wheel B6,v rigidlyfastenedonthe crank shaft IT.

For depressing'the valvestem ll of: the exhaust valve. a: cam 83 is rigidly fastened on the shaft 83, and has a tooth positioned to. engage the upper endof the valve. stem 11 during arevolution of the. crankshaft li. and of the; shaft. 8.3.

Aslshown inFig. 13,. the camtooth 90'first en-.- gages thevalve stem H and depresses-saidzstem, after which. while. it is so engaged, the tooth 82; of; the; cam 81 engages; and. depresses; the. valve 5116111712. These: engagements. are timed solthat;

of. explosive mixture enters the cylinder l ,,.above:-

the upper: piston 23- through the conductor. 3.3 and intake valve casingv 34, while. exhaust. gas pass-'- scope of .theappended claims, maybe made without departing from the spirit of my invention.

What I claim is: Y 1 In an explosive engine, an explosion cylinder having; end heads, one. of which has a tubularinward extension open at its ends, a piston head; reciprocative. in. said cylinder and having. an inner cylinder with an open end in which said. extension: is tightly reciprocatively fitted, the. other end of said; inner cylinder: being closed,

said piston head having a chamber encircling; said innercylinder, apistonrod, attached. to saidclosed end. and extending through said inner" cylinder and said extension,.means by which. a fluid may be admitted into and discharged from said. cham.'

her, and means for admitting propelling charges into and: exhausting; them from said explosion cylinder ataoppositeends of said piston head.

2: In an explosiveengine, in combination. with a crank case. having. cross head .guide supporting means,, cross head guides on said.- supporting, means, a wrist pin operatively engaging said. guides, acrank. shaft -rotative in said crank case,

said supporting means, a piston head recipro cative in said cylinder and having an inner cylinder tightly reciprocatively fitted on said tubular extension, and a iston rod attached to said piston head and extending through said inner cylinder and said tubular extension and operatively engaging said wrist pin.

3. In an explosive engine, two longitudinally alined explosion cylinders, each having end heads, the head of one cylinder forming the head at the adjacent end of the other cylinder and having a tubular inward extension open at its ends, the other head of said other cylinder also having a tubular inward extension open at its ends, two piston heads respectively reciprocative in said cylinders and having each an inner cylinder tightly reciprocatively fitted on the adjacent one of said tubular extensions, a piston rod integrally connected with said piston heads and extending through said inner cylinders and said tubular extensions and tightly reciprocatively fitted in said first named tubular extension, each of said piston heads having a chamber encircling its inner cylinder, and means by which a temperature controlling fluid may be admitted into and discharged from said chambers.

4. In an explosive engine, two longitudinally alined explosion cylinders each having end heads, the head of one cylinder forming the head at the adjacent end of the other cylinder and having a tubular inward extension open at its ends, the other head of said other cylinder also having a tubular inward extension open at its ends, two piston heads respectively reciprocative in said cylinders and having each an inner cylinder of said tubular extensions, a piston rod integrally connected with said piston heads and extending through said inner cylinders and said tubular extensions and tightly reciprocatively fitted in said first named tubular extension, means for admitting propelling charges into and exhausting the spent charges from said explosion cylinders simultaneously at like ends of said piston heads, each of said piston heads having a chamber encircling its inner cylinder, and means by which a temperature controlling fluid may be admitted into and discharged from said chamhers.

5. In an explosive engine, in combination with a crank case having cross head guide supporting means, cross head guides on said supporting means, a wrist pin operatively engaging said guides, a crank shaft rotative in said crank case, and a connecting rod connecting said wrist pin and said crank shaft, of two longitudinally alined explosion cylinders each having end heads, the

head of one cylinder forming the head at the adjacent end of the other cylinder and having a tubular inward extension open at its ends, the 

